Alkyl mercuric sulphur compound and process of producing it



Patented June 5, 1928.

PATENT OFFICE.

MORRIS SELIG KHARASCH, OF COLLEGE PARK, MARYLAND.

UNITED STATES No Drawing.

The present invention relates to alkyl mercuric compounds whiclreither are themselves water-soluble or have water-soluble salts, or both, and in which the mercury is bonded by onebond to a carbon atom of an alkyl radical; and to the process of producin such alkyl mercuric compounds.

ore specifically, the alkyl mercuric compounds which are produced by my invention have the mercury atom bonded by one bond to a carbon atom of an alkyl radical B, have the mercury atom bonded by its remaining bond to a sulphur atom, and have the sulphur atom bonded to a carbon atom of an organic radical R containing an acid group which has a free valence bond capable of being attached either to hydrogen or to a metal. The organic radical bonded to the sulphur may be either aromatic or aliphatic. The organic radical R which the present invention contemplates as being bonded directl to the mercur may be such radicals as t e methyl radical GH the ethyl radical C H the propyl radical C H,, the butyl radical C,H,, the amyl radical C H etc., or their isomers, or unsaturated aliphatic hydrocarbon radicals such as the allyl group CH =CH--CH but I prefer the lower hydrocarbons of this general alkyl class, and especially those having not to exceed three carbon atoms, and desirably those which have less than three carbon atoms such as the methyl and ethyl roups.

The final products contemplated y the present invention would thus have the following typical formula:

in which R is an alkyl radical, and R is an organic radical containing an acid group which has a free valence bond capable of being attached either to hydrogen to form the corresponding acid or to a metal to form a salt of such acid, and in which both the radical R and the radical RM, have carbon atoms bonded directly to the mercury atom Application filed June 29, 1927. Serial No. 202,468.

carbon atoms; and it is desirably of the paralfin series. The radical R is desirably an aromatic radical. Some of my more specific claims are directed to water-soluble salts containing the above radical; but the broader claims cover both the'acids and their salts.

In my Patent No. 1,589,599, granted June 22, 1926, I describe ageneral method whereby organo-metallic compounds can be introduced into water solution by the use of acids containing sulfhydryl groups; which in cludes thioglycollic acid, the various sulfhydryl butyric acids, the various sulfhydryl propionic acids, thiomalic acid, thiosalicylic acid, p-sulfhydryl benzene sulfonic acid, mercapto-benzothiazole carboxylic acid, p-sulfhydryl phenyl acetic acid, cysteine, and substitution products of. such acids, as well as other compounds containing a sulfhydryl (-SH) group" or groups and an acidic group or grou s such as the-carboxylic group (CO H) or the sulfonicgroup (SO,H). .That patent, although including claims covering generically-certain water-soluble organo-mercuric compounds and the process of producing them, whether the organic radical directly attached to the mercury was aromatic oraliphatic, was directed in its more specific claims tomercury compounds in which such organic radical directly attached'to the mercury atom was an aromatic radical, such as the phenyl radical; so that clalms directed specifically to such mercuric compounds,

when the organic radical directly attached to the mercury atom was an alkyl radical could not be obtained therein. This present application, on the other hand, is directed specifically to such organo-mercuric compounds in which the organic radical directly attached to the mercury atom is an alkyl radical; and contemplates generally such organo-metallic compounds when the mercury is attached to sulphur and the sulphur is attached to an acid group of the general Ly es mentionedabove.

n producing these new products, I treat a suitable alkyl mercuric compound with ter-soluble salt salt, desirably using the sulfhydryl organic acid. This may be expressed by the following general formula:

in which R is an alkyl radical having a carbon atom directly. bondedto Hg, R is an. organic radical having a carbon atom directly bonded to S and containin an acid group which has a freevalence 0nd capable of being attached either to hydrogen to form the. corresponding acid or tea metal to form a salt of such acid, Y is an inorganic radical of other than the sulphur family (such for instance as C1 or OH) or an organicacid radical (such as the acetoxy radical --OCOCH,,), and Z represents either hydrogen or a monovalent metal or an equivalent I polyvalent metal or a monovalent non-metal basic radical. In thereaction, I prefer that Z'shall be hydrogen, so that the initial sulfhydryl organic compound will be an acid. In carrying out the reaction, I prefer to prevent the formation in the final result of any free by-pro'duct acid, (and if desired of any acid,) for which purpose it is desirable either that Y be thefhydroxyl group -OH or that a base be provided as a third reacting com ound, as for instance by using one or two or-more) molecular equivalents of sodium hydroxide or sodium bicarbonate; or Z may be a monovalent metal or basic radical. I

The product is into water,-

upon the methyl mercuri-thios'alicylic acid is precipitated, since it is insoluble in water. H hisprecipitate can be collected .on a filter, and washed well with water to remove all the alcohol, salts, and free inor anic acids. The washed precipitate may t en be dissolved in a water solution of sodium hydroxide, or, better, in a water solution of sodium bicarbonate. This produces the we- The methyl mercuri thiosalicylic acid is a white solid which melts at about 171 C. It is soluble in aleohol'and in'ether. It is a) OBkHgOl amen:

coon

H O QBWO-+ moi me.

While many other examples of my inve'n- Q tion might be given, I 've below a few examples of products invo ving the present invention andthe methods of preparing such products.

In carrying out the present invention, I prefer to carry on the condensation with acohol rather than with water as the condensing medium or solvent; although in many nstances 1 desirably use water and alcohol to ether, and although my invention broad y contemplates the use ofv any suitable condensing medium or solvent, such as water, alcohol, or acetone. My invention contemplates the use of either the sulfhydryl acids or their salts as the initial sulfhyd'ryl compounds used. in the process.

"The following examples are merely illustrative of my invention:

Emarmple 1.

0.1 mole of thiosalicylic acid (HS-C,H,

COOH) in alcohol. The condensation takes place in this manner&

coon

. Ewample 2. p If desired, the water-soluble salts mentioned above may be prepared directly, by

a process similar to that outlined in Example 1, save that two or more molecular proportions of sodium hydroxide are used instead of. one. In that case, the reaction will be as follows:

To isolate the sodium methyl mercurithiosalicylate in a form in which it will be suitable for injection, the whole mixture is poured-into an excess of water, filtered if COONa Eat-ample H.150 -0 OHaHI necessary I and the filtrate acidified with either sulphuric or hydrochloric acid. With siilphuric acid, the following reaction. takes p ace:

curic chloride of Examples 1 and 2, one may start with other methyl mercuric compounds, such for instance as methyl mercuric hydroxide. If that is treated with thiosalicylic acid, conveniently in alcohol as a condensing medium, the following reaction takes place:

Instead 0f starting with the methyl mer- (1) crim on no OEhHgSO nlo.

The methyl mercuri-thiosalicylic acid formed may be purified and a water-soluble salt obtained therefrom, in the manner outlined in Example 1.

The foregoing examples will suggest various other modifications of the samegeneral method to a person skilled in the art.

In the foregoing three examples, it is contemplated that the thiosalicylic acid will be thiosalicylic acid. This may be isolated and purified as in Example-2.

The same processes may be usedwith different initial alkyl mercuric compounds, such for instance as the ethyl mercuric, propyl mercuric, butyl mercuric, amyl mercuric, or allyl mercuric salts or hydroxides,

- or their isomers; and with various thio acids 50 such as those named earlier,'including not only the thiosalicylicacid given in the above examples but also (among others) thioglycollic acid, p-sulfhydryl phenyl acetic acid, p-sulfhydrylbenzen'e sulfonic acid, ,8 sulfhydryl propionic acid, sulfhydryl butyric acid, and cysteine. I shall not attempt to enumerate all the diiferent acids and salts thus obtainable by difierent pairings of such initial compounds, as that will be evident from what has been said.

Generally speaking, the mercuri-thio acids obtained are water-soluble when the acid group is of the sulfonic series, and usually water-insoluble when the acid group is of the carboxylic series; but the sodium, potassium, ammonium, and salts of said mercurithio acids are water-soluble in all instances. In all the examples given using carboxylic thio acids, the thio acids used as illustrations were ortho acids, with the sulfhydryl group and the carboxylic group joined to ad]acent carbon atoms of the benzene ring. However, this was merely illustrative, as the analogous meta acids and para acids may be used equally well.

Similarly, in the various other aromatic acids named,.the sulfhydryl group and the acidic group may .be in either the ortho, meta, or para relation. This is so both with the carboxylic acids and the sulfonic acids.

While in man cases it is desirable to prevent the formatlon in the final result of any free by-product-acid, as by having a hydroxyl group for Y or b conducting. the reaction throughout in t e presence of free hydroxyl ions, in certain cases the condensation may be effected without the presence of any base as a condensing agent. For example, one may take a solution or suspension of 0.1 mole of ethyl mercuric chloride (C H H C1) in alcohol and treat it directly with a so ution or suspension of p-sulfhydryl benzene sulfonic acid in alcohol. A white precipitate separates on short standing, which is the condensation product. The reaction takes place in the following manner:

a am o; nPO-souacameo-com H01 cium.

The ethyl mercuri-p-s ulfoben zene sulfonic acid thus formed as the ,white preci itate is separated by filtration, and may be issolved in a water solution of sodium hydroxide or sodium bicarbonate as before, toproduce a solution of the sodium salt suitable for injection.

Ethyl mercurl-p-sulfobenzene sulfonic acid CaHsHZSO S0111 is a white solid, and has no melting point up to about 300 C. It is soluble in water and dilute hydrochloric acid. It is insoluble in alcohol and ether. It forms water-soluble salts with the alkali metals, such as-sodium and potassium, with ammonia, and with some (probably all) alkyl-amines; and

water-insoluble salts with the alkaline earth metals, such as calcium.

I give below a fewexamples of mercurithio'acids which have been produced by obvious modifications of the processes outlined in Examples 1, 2, and 3:

- Ethyl mercuri-thiosalicylic acid coon CQHEHENSO is a white solid which melts at about 110 It is insolublesin water and dilute hydrochloric acid. It is soluble in alcohol and ether. It forms water-soluble salts with the alkali metals, such as sodium and potassium,

with ammonia, and with some (probably all) alkyl-amines; and water-insoluble salts with the alkaline earth metals, such as cal- Ethyl mercuri-m-sulfobenzoic acid QunH sOoooH is a white solid which melts at about C.

It is insoluble in Water and dilute hydrochloric 'acid. It is soluble in alcohol and ether. 'It forms water-soluble salts with the alkali metals, such as sodium and potassium. with ammonia, and With some (probably all) alkyl-amines; and Water-insoluble salts with the alkaline earth metals, such as calcium.

Isoamyl mercuri--flsulfopropionic acid otunn s-omomcooa is a white solid which rcddens at-about 160 (3., blackens at about 210 (1., and melts with decomposition at about 215 C. It is insoluble in water and dilute hydrochloric acid. It is soluble in alcohol and ether. It forms water-soluble salts with the alkali metals, such as sodium and potassium, with ammonia, and with some (probably all) acid, alcohol, and ether.

alkyl amines; and water-insoluble salts with the alkaline earth metals, such as calcium.

Isoamyl mrcurl-cysteine hydrochloride C6HIIH8SCHl-OHQOOH NHn-HCI v is a white solid which melts at'about 95 C. It is insoluble'in water and dilute hydrochloric acid. It is insoluble in alcohol and ether. It forms water-soluble salts with the alkali metals, such as sodium andpotassium, with ammonia, and with some (probably all) alkyl-amines; and water-insoluble salts with the alkaline earth metals, sueh as calcium.

Ally] mercurtcystelne hydrochloride 5 cm=ca-cH.-u s-cm cH-ooon is a White solid which melts with decomposition. It is slightly soluble in Water and dilute hydrochloric acid. It is soluble in alcohol and ether. It forms water-soluble salts with the alkali metals, such as sodium and potassium; and waterinsoluble salts with the alkaline earth metals, such as calcium.

is a white solid which melts at about 73 C. It is soluble in water, dilute hydrochloric acid, alcohol, and ether. It forms watersoluble salts with the alkali metals, such as sodium'and potassium, with ammonia, and with some probably all alkyl-amines; and water-insoluble salts Wit the alkaline earth metals, such as calcium.

' Ally] mer'curi-p-sulfobenzene sulfonic acid is a white solid, and has nd melting point up to about 300 (1. It is soluble in waterand dilute hydrochloric acid. It 'is insoluble in alcohol and ether. It forms watersoluble salts'with'the alkali metals, such as sodium and potassium; and water-insoluble salts with the alkaline earth metals, such as 'calc1um.

- Methyl mercuri-thioglycollic acid CH HgSCHzCO0H is a white solid which melts at about 79 c.

at about 93 C;

Ill

It is soluble inwater, dilute hydrochloric acid alcohol, and ether. It forms watersolu 1e salts with the alkali metals, such as sodium and potassium, with" ammonia, and with some (probably all) alkyl-amines.

Propyl mercurl-thloglycollic acid C,H-,Hg'SCHz-CO0H is a white solid which melts at about 73 C. It is soluble in water, dilute hydrochloric acid, alcohol, and ether. It forms watersoluble salts with the alkali metals, such as sodium and potassium, with, ammonia, and with some (probably all) alkyl-amines.

n-hutyl inercuri-thioglycollic acid C H Hg-SCHaC00H 'lllthyl mercuri-B-sultopiopionic acid. cmsn s -cmclarcoon n-butyl mercuriasultopropionic acid.

C H HgS-CHICH,COOH

' Ethyl mercuri-cysteine hydrochloride.

n-butyl mercuri-cysteine hydrochloride. c;H.H --s -cH,-cH cooH Ethyl mercurbsultosuccinic acid.- C H;Hg -SCH-COOH Ha-COOH n-butyl mercuri-thiosalicylic acid.

/ COOH Ethyl mercuri-m-sultobenzoic acid.

Butyl mercuri-msulfobenzoic acld.

ChHuHg-B-O-OOOH Ethyl mercurl-p-suliobenzoic acid.

cams-s-O-ooon Butyl mercuri-p-sultohenzoic acid.

airba -0003 Isoamyl mercurl-p-sultobenzoic acid.

ClHllHE-SO-COOH Ethyl mercuri-p-sultophenyl acetic acid:

c,mn -s'-Oomooon Methyl mercurl-p-sulfobenzene sulfonic acid.

CHaEiG-S-O-BOaH Allyl mercuri-thiosalicylic acid.

COOK

. on, on-ommwa-O Ethyl mercuri-p-sulfosalicylic'acid.

clmnz-eQ-on OOH n-hutyl mercuri-p-suli'osalicyllc acid.-

(In preparing most of the substances just named, initial sulf-hydryl organic compounds are usedthat are known and available. However, in preparing the last two of the list, an initial sulf-hydryl organic compound 1s used that I believe is itself new It is p-sulfhydryl salicylic acid n-sQon oon It is prepared by diazotizing; amino salicylic acid in the regular, manner. The diazo compound is then neutralized with sodium bicarbonate, and the r uisite amount of potassium xanthate adde The solution 1s boiled with alkali to hydrolyze the xanthate addition product, and the sulfide recovered by'acidification and filtration. T

The sulfide is then reduced with sodium As already indicated, the alkali-metal salts of these various acids are all water 'soluble.

The sodium salts are well-suited for intravenous injection. These water-soluble.

.. salts are eflective therapeutically as germicides.

I claim as my invention r 1.- A step in the method of producing wa ter-soluble compounds of alkyl mercuric compounds, which comprises treating, in a suitable solvent, a mercuric compound in which one valence bond of the mercuryis attached to a radical of other than the sulphur family and the other valence bond of the mercury is directly attached to a carbon atom of an alkyl radical, with an organic compound containing both an acid radical and a sulfhy'dryl group and having the sulfhydryl group directly attached to a carbon atom. i

2. The step in the method of producing water-soluble compounds of alkyl mercuric compounds, which comprises treating, in a suitable solvent, a mercuric compound in which one valence bond-of themercury is attached to a. radical of other than the sulwhich one valence bond of the mercury isphur family and the other valence bond. of the mercury is directly attached to a carbon atom of an alkyl radical of the paraflin series, with an organic compound containing both an acid radical and a sulfhydryl group.

and having the sulfhydryl group directly attached to a carbon atom.

3. The step in the method of producing water-soluble compounds of alkyl mercuric compounds, which comprises treating, in a suitable solvent, a mercuric compound in which one valence bond of the mercury is attached to'a radical of other than the sulphur family and the other valence bond of the mercury is directly attached toa carbon atom of an alkyl radical having not toexceed three carbon atoms, with an organic compound containing both an acid radical and a sulfhydryl group and having the sulfhydryl group directly attached to a carbon atom. o I

,4. The step in the method of producing water-soluble compounds of alkyl mercuric compounds, which comprises treating, in

alcohol as a condensing medium, a mercuric having the sulfhydryl group directly attached to a carbon atom;

5. The step in the method of producing water-soluble compounds of alkyl mercuric compounds, which comprises treating, in alcohol as a condensing medium, a mercuric compound in which one valence bond of the mercury is attached to a radical of other than the sulphur family and the other valence bond of the mercury is directly attached to a carbon atom of an alkyl radical,

with an organic compound containing both an acid radical and a sulfhydryl group arid ha-vin the sulfhydryl group directly attache to acarbon atom,

6. The step in the method of producing water-soluble compounds of alkyl mercuric compounds, which comprises treating, in a suitable solvent, an alkyl mercuric salt in which one valence bond of the mercury is attached to a radical of other than the sul hur .family and the other valence bond 0 the mercury is directly attachedto a carbon atom- 7. The step in the method of producing Water-soluble compounds of alkyl mercuric.

compounds, which comprises treating, in ,a'

suitable solvent, an alkyl mercuric salt in attached to a radical of other than the suland a sulfhydryl group and having the sulfhydryl group directly'attached to a carbon atom, in thepresence of a substance which neutralizes acid formed in the reaction.

8. The step in the method of producing water-soluble compounds ofalkyl mercuric compounds, which comprises treating, in a suitable solvent, an alkyl mercuric compound having one valence bond 'of'the mercury attached to a radical of other than the sulphur family, with an organic compound contain:

ing both an-acid radical and a js ulfhydr 1 group and having the sulfhydryl group irectly attached to a carbon atom, and including a monovalent base in the reaction.

9. An alkyl mercuric compound, in which one bond of a mercury atom is attached to a carbon atom of an alkyl. radical, the other bond of the mercury atom is attached to one bond of a sulphur atom, and the otherbond of the sulphur atom is attached-to a carbon atom of an organicradical'corttaining an acid group which has a valence bond capable of being attached either to hydrogen or to a metal. J

10. An alkyl mercuric compound,in which one bond of a mercury atom is attached to a carbon atom of an alkyl radical, the other bond of the mercury atom is attached to one bond of a sulphur atom, and the other bond of the sulphur atom is attached to a carbon atom of an aromatic radical containing an acid group which has a valence bond capa ble of being attached either to hydrogen or to a metal.

11. An alkyl mercuric compound, in which one bond of a mercury atom is attached to a carbon atom of an alkyl radical of the parafiin series, the other bond of the mercury'atom is attached to one bond of a sulphur atom, and the other bond of the sulphur atom is attached to a carbon atom of an organic radical containing an acid group which has a valence bond capable of being attached either to hydrogen or to a metal.

12. An alkyl mercuric compounrhin which one bond of a mercury atom is attached toiacarbon-atom of an alkyl radical having not to exceed three carbon atoms. the other bond of the mercury atom is attached to one bond of a sul hur atom. and the other bondof the sulp ur atom is attached to a carbon atom of an organic "radical containing an acid group which has a valence bond capabio of being attached either to hydrogen or to a metal.

13. An alkyl mercuric compoumhin which one bond of a'inercury atom is attached to a carbon atom of an alkyl radical of the paraflin series. the other bond of the mercury atom is attached to one bond of a sulphur atom, and the other bond of the sulphur atom is attached to a carbon atom of an aromatic radical containing an acid group which has a valence bond capable of being attached either to hydrogen or to a metal.

- 14. An alkyl mercuric compound. in which one bond of a mercury atom is attached to a carbon atom of an alkyl radical having not to exceed three carbon atoms. the other bond of the mercury atom is attached to one 16. A water-soluble alkyl mercuric salt, in which one bond of a. mercury atom is attached to a carbon atom of an alkyl radical, the other bond of the mercury atom is at tached to one bond of a sulphur atom, and the other bond of the sulphur atom is attached to a carbon atom of an aromatic phur atom is attached to a carbon atom of .an organic radical containing an acid group which has a valence bond attached to an alkali metal.

18. A water-soluble alkyl mercuric salt,

in which one bond of a mercury atom is attached to a carbon atom of an alkyl radical having not to exceed three carbon atoms. the other bond of the mercury atom is attached to one bond of a sulphur atom, and the other bond of the sulphur atom is attached to a carbon atom of an organic radical containing an acid group which has a valence bond attached to an alkali metal.

19. A water-soluble alkyl mercuric salt, in whichv one bond of a mercury atom is attached to a carbon atom of an alkyl radical of the parafiin series. the other bond of the mercury atom is attached to one bond of a.

sulphur atom, and the other bond of the sulphur atom is attached to a carbon atom of an aromatic radical containing an acid group which has a valence bond attached to an alkali metal.

20. A water-soluble alkyl mercuric salt, in

bOIld Of a sulphur atom,.and the otherbonds hi h one bond of a mercury atom is atof the sulphur atom is attached to a carbon atom of an aromatic radical containing an acid group which has a valence bond capable of being attached either to hydrogen or to a. metal.

i 15. A water-soluble alkyl mercuric salt, in which one bond of a mercury atom is attached to a carbon atom of an alkyl radical, the other bond of the mercury atom is attached to one bond of a sulphur atom, and the other bond of the sulphur atom is attached to a carbon atom of an organic radical containing an acid group which has a valence bond attached to an alkali metal.

.tached to a carbon atom of an alkyl radical having not to exceed three carbon atoms, the other'bond of the mercury atom is'attached to one bond of a sulphur atom, and the other bond of the sulphur atom is attached to a carbon atom of an aromatic radical containing an acid group which has a valence bond attached to an alkali metal.

. In witness whereof. I have hereunto set my hand at Indianapolis, Indiana, this 27th day of June, A. D. one thousand nine hundred and twenty seven.

MORRIS same KHARASCHQI 

